diff --git a/pyproject.toml b/pyproject.toml
index cc5336d..f3a36a8 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -43,7 +43,7 @@ Changelog = "https://github.com/common-workflow-language/cwl-utils/releases"
 [project.optional-dependencies]
 pretty = ["cwlformat"]
 testing = [
-    "pytest<9",
+    "pytest<10",
     "pytest-mock",
 ]
 
diff --git a/test-requirements.txt b/test-requirements.txt
index 6ca7d9a..8a3abf8 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,4 +1,4 @@
-pytest < 9
+pytest < 10
 pytest-cov
 pytest-xdist[psutil]
 cwlformat